Selective separation of liquids



Aug. 23, 1932. A. JOHNSON SELEGTIVE SEPARATION OF LIQUIDS Filed Dec. 12, 1924 @mmf/MM Paienie Aug. 23, 1932 Anuman Joirirsoiv,` orA Wnsrnni.nien",` NEW YORK, `Assis-non rroV corinusrion criti- 'rins coaroiaa'rioiv, 'or NEW YORK, iv. Y., A-oonroaafrioiv or Marmi sELnc'rivE sEiuinnrnjiiv` or 'traumas Application iled December 12, 1924. Serial No. ,755,375

This invention relates to the separation'of i liquid emulsions into their constituents, and

inoreparticularly to a method of and apparatus for dehydrating tar-Water emulsions or similar aqueous emulsions of fatty or resinous Great difficulty is often encountered in breaking dovvn liquid emulsions and selectively separating their several constituents. This is particularly true of aqueous emulsions of colte-oven or Water-gas tarsand petroleum oils. In a tar-water emulsion the Water is n ormally the low boilingandthe `tar the high boiling constituent of the emulsion. One` of the greatest problems a tar distiller has to' `face is the elimination of Water, Which is `present in proportions ranging from to in almost all tars.

Before submitting Wetter to distillation it is desirable andin the case of some tars absolutely necessary `to separate water from the tar to prevent foam ing and priming in the still, and more generally in order that the distilling plant will not. be too cumbersome and expensive inde-` f sign and in operation. Sonie tars canbe dehydrated by simple settling, but as a rule the Water and tar mixture forms an emulsion which cannot be broken down `even afterlong 'standing Ordinary methods of distillation are as a rule ineffective for breaking down emulsions. I Mechanical disintegrators and centrifugal separators are `often employed for dehydrating tar, but the cost of install- -ing these special classes `of dehydrators is `a relatively lovv treating capacity.

rhigh, and they are expensive to operate.

As a rule they require `batch or intermittent charging and discharging, and therefore have The primary cbj ect of the present invention jis to provide a method and apparatus by means of which liquid emulsions can be continuously and rapidly resolved and the emulsion constituents separated.

Vth this object in view one vapor of its loW boiling constituent, so that nthe gas Will selectively vaporize the 10W boileof-ing ,constituent Without having a substantial feature of the l`-invention contemplates intimately contactuents of the emulsion.-

Another object of the invention is to pro` vide a simple, eifective and economical meth-` od of and apparatusfor separatingwater from Wet tar or similar aqueous emulsions.

VTo accomplish this object another'feature of the invention contemplates usingV the hot tar vaporcarrying gas removed from a gas generator as a deliydratingagent,` andsimultaneously making use of the Wettar or other aqueous emulsion which is to be dehydrated` as a condensing'and scrubbing agent for cool-V ingtheigas and scrubbing outitscondensible higliboiling constituents. Y

With these and other objects and features. in View, the invention consists inthe method of and apparatus for selectively separating" the constituents Vof liquid emulsions hereinafter described and particularly dened in the'claimsl* 1 The'various features of the invention are illustrated in the accompanying dravving,` which represents in vertical elevation, partly in section, the arrangement of dehydrating apparatus `embodying the preferred form of the invention. Y

Essentially the preferred dehydrating method consists in contacting a circuit of gas heated to a temperature above the boiling point of Water and unsaturated With Water vapor at the temperature employed With an atomized emulsion consisting vof Water and some other fatty or resinous constituent of a highly boiling point, in ascertained ratios byA volume and for a period of time such that the sensible heat of the gas will besufiicient to effect a complet-e separation and vaporization of the Water from the emulsion-without completing saturation of the gas at the tem peratures obtaining at the close of the dehy` drating operation. Among the Ymany ativantages which may be claimed for this novel procedure'are that an aqueous 'emulsion can be completely and effectively dehydrated Without appreciably effecting its higher boiling'constituents; that both the new process and 4the neviT apparatus'fare exceedingly" simple and may be run continuously 4or intermittently with equal facility; and that the vaporizing effect onfhigher boiling constitf` new process and apparatus can be combined readily with the condensing, scrubbing and tar extracting steps of a tar vapor carrying Agas scrubbing operation to materially 1ncrease the economy and efficiency of thetar dehydration and also of the gas scrubbing operation. 1

The arrangement of apparatus illustrated in the drawing shows the application of theV invention vto the .dehydration of a tar-water emulsion when the rich or tar vapor carrying gas taken oli'l from the top of a shaft generator of the type known as the Doherty gas shell is employedy as a dehydrat-ing agent. The preferredv method of dehydrating tar-water emulsions, as carried out in the apparatus illustrated in the drawing, consists in remov-v ing the rich gas evolved from coal or other carbonaceous material during its Vdistillation in the upper portion of a shaft generator orV carbonizing shell 10, Vwhile at a temperature of about 500 F., Vthrough a gas offtake 12,

lpipe 18 `and a spray nozzle 20.

`The rich'hot unpuriied coal distillation gas removed from the top of a generator of the Doherty shaft type,`operating with charges of bituminousffuel on a modified water-gas or` lhydrogas process, at 500 carries an averageof about eight pounds of water and about five pounds of con'densible volatile compounds, or tar, per 1000 cubic feet of gas. The dew point lfor a gas of the above type containing eight pounds of water per 1000 cubic Vfeet is approximately 128 F. Accordingly, every thousand cubic feet of such a gas when superheated to a temperature of 500 F. can be used to evaporate approximately seven `rpou-nds of water in cooling from 500 F. to

148 F., which is the approximate dew point of such a gas containing fifteen pounds of water.

- In passing downwardly through standpipe 16 the *hotV rich gas is brought into intimate contact with the downwardly moving tarwater emulsion, which is in an atomized condition or Iin thin layers by reason of itsl introduction throughspray nozzle 20 and its distribution over baflies 22. As a result of this intimate contact, the gas is cooled by a direct heat transfer with the wet tar emulsion andthe sensible heat thus given up by thek gas evaporates the water constituent of the emulsion. The dry tar follows down along the side of the standpipe and drains into a dry tar tank 24 from which it may be removed through an off-take pipe 25. The tar collected intank 24 serves as a gas seal for the standpipe, while the gas, substantially saturated with the water it has picked up in the standpipe 16, passes through vmain 26 into the base of a standard type of con densing and scrubbing unit 28. As it rises 'upwardly through filling 30of this condensvonf a similar condensing unit 38, where any tar or lother Vcondensible liquid remaining in thegas is condensed out or precipitated as the' @as rises throuOh lillinoP 40 b direct con-v tact with sprays and films of cooling water introduced through a pipe 42 and nozzles 44. l

The scrubbed gas is then removed from the top of unit 38 through a Ymain 46 into an exhauster 48 and is preferably passed through light oil scrubbing and purifying equipment and thence into storage holders or service mains (not shown).

The tar and water condensed and scrubbed out ofthe gas in the units 28 and 38, together with any emulsion formed or deposited therein, is passed through pipes 50 and drawof pipe 52 into one end of a tar separator 54.

The liquid mixture is directed by verticalY baffles 56 to follow a zigzag path as it flows from one end-of tank 54 to the other, any water or ammonia liquor which separates from the tar is drawn off through outlets 58. From the other end of tank 54 the wet tar is drawn through a syphon 60 into a tar decanting tank 62, from which asmuch water as itis possible to separate from the tar by gravity settling during the short period of time available is removed through drawoff pipes 64 and valves 66 into a vertical extension 68 of ammonia liquor main 70. The semi-dry tar is then removed from the tank 62 through pipes 72 and valves 74 into main 7 6, and is forced by pump 7 8 into the base of tank 80. From tank the semi-dry tar is forced by pump 82 through the feed pipe 18 and spray nozzles 20 into the top of the stand-pipe 16.

A valve 84 in feed pipe 18 is preferably actuated automatically by some form of temperature regulator such as that indicated da` grammatically in the drawing. The type of regulator usedis optional so long as it performs the function required of it. rlhe type of regulator illustrated in the drawing comprises essentially a thermostat 86 placed in the gas conduit`26 and arranged to close or open a switch 88, by which an electric circuit is in turn opened or closed and a solenoid 90 is excited to draw a rack plunger 92 back and forth through its core. The thermostat 86 is usually set to operate within slight temperature changes; that is, whenever the temperature of the gas passing through line 26 is lowered or raised, if only to a slight degree,

neo

. 192 engage theteethof a pinion 94 on the such variatior ,will besuicient to i set thel regulator i in` motion.` The e teeth `of plunger stem ofthevalve 84 land;themovement of fthe fplungertopens or closes the valve. The

` e chietpurposeofgthis,temperature regulator;

fia

fis to `so control `the lrate of flow. of semi-,dry

to. collect onlyI dry tar in tank; 24. n Accordingly, the ,vo-lumeof the semi-dry tarsprayed intothe gas stream atthe top of the stand- Apipe should `preferably be kept low enough so `that its `water contentgcan all be evapo-V ratedbyVthe heat of the gas without lower- H ing the temperature of the gas below the dew point. For econcmuical e operation, however,

`it fisalsoimportant that `the gas leave the ,base ofthe standpipe without any considerable degree of superheat. If the gas is aly lowed -toleavewith considerable superheat light hydrocarbons may be evaporate-.d freni `thetar Aand carried on into the condensing systern.V ,The `water `,contentin the semi-dry tar or the'yolume of -tar to be treated, may not alwaysbe sufcientito lower the temperature ofthe gas the desired amount during its lpasV sage 1through the standpipe. Accordingly, as

an additional means of controlling the teinperature of` gas y, leaving the standpipe through "conduit 26, awater circuit isiprovided comprising an `intake pipe96 leading to a `spray nozzle 98 in the top oi. standpipe `16,.` valve 100 inthe water intake pipe is actuated automaticallyby the saine tem.

perature `regulating :device which actuates valve L84 in the semi-dry tari'eed line. `By opening i or closing valveV 100` regulated amounts `oi watercan be addedwto the gas atthe top of the standpipe tomalre up any deficiencies in Jshe volume of water carried by the semi-dry tar,` sothat Vthe gas `will always enter the condensing system approxi# mately; saturatedwith watervapor and ata `uniformtemperature which is only slightly above its dew point. i In its 1 downward passage through `the standpipe 16 `therich gas dehydratingimedium drops mostiof its dustcontenandas its-temperature is lowered, quite a large proportion of thehigh boiling hydrocarbons which it carries condensein the form of tiny globules or tar inist and are scrubbed out by `the tar undergoing dehydration. Y Thns one ofthe chief advantages ofthe invention is that while the dehydration is taking place the tarnndergoingdehydration is used si,-

rnultaneously` as `a scrubbing and condensing l"agent for rernovingsdust and high boiling tar. emulsions can be carried on simultanen ously witha gas condensing and tar scrub,g bing operation, within the `confines of a single set `oi apparatus units whichY are eX- treinely simple and :inexpensive both in design and operatiomthus-y reducing mate=` rially both the'cost of dehydrating theernul- Vsions and-the costof'lprepafingfthe gasforV industrial ondornesticusef i L- i he method'gand apparatus describedand illustrated e in the drawingqis notliinited to the treatmentvoi aqueous coal-tar ,emule sions, but may` be applied with slight modification in design to the dehydration of many other Alindsoit aqueous emulsions. Thus the same procedure `may be applied, usinglsubstantially the apparatusillustrated, tothe Y dehydration e of water-gas tar emulsions with water-gas, as by fcirculating the Vllllllon` through the water jseal boX and/or through the entrance pipe tothe seal.` The gas de hydrating medium4 which is Aemployed need not be a richcoal gas such as that,removed` from a Dohertyicarbonizing shaft operating on `aniodied water gas orffhydrogaso proc,- ess.1 e `The principalreason for choosing such a gas ini describingjthe preferred form of the invention was yto illustratezhow a gas `which is already partially saturated with water vapor y andicondensible hydrocarbons "can, be used as a dehydrating agent whilebeing simultaneously condensed 4and* partially scrubbed by a previously condensed semi-dry coal tar.` A clean,dry gas would ofcourse be far more effective as adehydrating agent, but in using such a gas the :cost of preheating Vneeds as a ruleto be considered.` It has been found that in operating Doherty gas shells, lfor instance, the temperature of rich v gas leaving the top oi the shell cannot be reducedrnuch below 500 F., so that by using such a gas asa `dehydrating agent the expense involved:in ,preheatingthe gas dehydrating Y agent `is notonly avoided but a Inajorlpart of the heatfwhich would otherwise be lost from the gas maltingoperatio-n in the form of sensible heat carried out by the rich gases is by this means recovered and utilized, thus raising the thermal eciency of the combined i gas noa-king, gasscrubbing and tar dehydrat ing operations.` 'y i Y j i n.

Onefeature of the invention is that the gas and emulsion `are passed in the saine direction `through the dephlegmating shaft. The advantageo thus passing the gas and emulsion in parallel is that the temperature Vof the. gas as it enters andlleaves the shaft can always be maintained below the boiling point ,of the `high-boiling constituent of the emulsion .without `materially impairing pits,

limited tothe particular type illustrated Vdiagrammatic'ally in the drawing. ri'his tem# centage of the light hydrocarbon constituents of the tar to be carried olf with the gas into the 'condensing system, if desired.

The new apparatusis extremely simple and consumes'relatively little time, power or heat operation. Every unit volume,'or 1000` eu. ft. of afpart'ially saturated fuel gas of the class described, for example, containingsay eight pounds of water and five pounds of tar, when contactedgwith a stream of water-tar emulsion at a temperature of 500, assuming f the emulsion vtobe at 60 F., is capable of dehydrating about sixteen pounds of tar .from

an emulsion-containing 30% water, in cooling to a temperature of 148 F. anY operation in'fwhich the whole supply of wettar to be dehydrated is originaliy obtained from vthe dehydrating gas current itself, it is apparent that the dehydrator need be in operation less than one-third of the time. This yoperating period Ais further'shortened .z due to the fact'that a part of the tar carried bythe gas is always Condensed out andV precipitated in the form of dry tar within the` standpipe of the dehydrating unit itself. i

` The speed at which exh auster 48 is operated controls the rate at which the tar'vapor cary rying fuel gas is drawn through the vdehydrating unit 16 and through condensing and scrubbing units 28 an dv 38, and the per'iodduiing which gas and emulsion are contacted in the shaft 1 6 is therefore controlledfby the' eX haustier. The volume ratio and temperature differential between gas and wet tar entering theV standpipe 16 are preferably maintained n high enough so that the current of gaswill give up sufficient sensible heat during its passage through the standpipe to evaporate all the low-boilingl constituent, e, g; water, from the tar-water emulsion without at the same time becoming saturated therewith. However, ifatany'time the volume ratio between gas and tar, orthe temperature differential between ill-gOng gas and wet tar, respectve ly',- fall below those preferred for complete dehydration conditions, the apparatus Vmay -be preferably so arranged that any tar which is not dehydrated in the first treatment can be re-circulated through the dehydrating unit in direct Contact with a fresh current of dry or partially dry hot gas. For this purpose the same single unit 16 may be used, or

two or more of such units may be arranged in'series, in parallel, or in any other convenient way in which they can be connected upto carry out mos't'effectively and economilcally the' complete dehydration of a given tar partial purification' of a Accordingly, in

and/or vthe simultaneous condensation and particular gas dehydrating agent.

The new and useful method andapparatus above described is not limited to the dehy-l dration of aqueous emulsions, but may be-apperature 'control feature may be Vadvanta` geously extended soas to permit a certain perf i. which will serve selectively to evaporate one constituent of the emulsion in preference to other higher boiling constituents.

In the specification and claims the medium employed for breaking down the emulsionV and causing selective separation of its con-v stituents has been described as a: gas containing superheat with lrespect to the vapor of the low-boiling constituent.7 This phrase is employed generically to describe a gas heat-ed to a temperature above theboiling point of the low-boiling constituent of the emulsion and unsaturated with respect tothe vapor of said low-boiling constituent.

The preferred form' of the invention having been ythus described what is claimed as new is: f y

l. A method of dehydrating aqueous emulsions which comprises atomizing va regulated volume of the emulsion into a current of gas containing superheat with respect to waterY vapor, dispersing the emulsion through the hotV gas and passing both downwardly throu h a dehydrating shaft in direct heat transferring relationship to evaporate water from the emulsion, removing Ymoist gas Vand dry constituents of the emulsion separately4 from the base of the shaft, and maintaining the'teinperatui'e of the gas leaving the base of the shaft above its dewpoint,

2. A method of dehydrating aqueous emulsions which comprises atomizing a regulated volume of the emulsion into a current l0f gas containing superheat with respect to water vapor, dispersin the emulsion tliroughthe gas to evaporate 4water therefrom and tosiinultaneous'lyv cool andpurify thegas by scrubbing out its condensible c omponents,

subsequently separating the dry constituents of the emulsion from the moist gas, periodically introducing additional water into the l-'ifi water are introduced `into the gas according to the temperature of the separated moist gas. ,'-iir 3. A method of dehydrating tar Vwhich comprises atomi'zing a regulated volume of wet tar into a current of hot dry fuel gas, passing the latomized tar and gas' through a dehydrating shaftin intimate heat transferring rela- Fll tionship to evaporate water from the tar and simultaneously to condense and scrub out high A boiling hydrocarbons from the gas, collecting dry tar at thejbase of the shaft and removing moist gas separately from the shaft at a teinsy perature slightly alcove *its `dewpoint, `controlling the temperature of the out-going gas,

Y fand governing the rate `at which tar is introduced` into the shaft according tothe temperature ofthe out-going gas.`

" i 4. 'A method of leh drating tar which com"- vprises` introducing regulated portions of` hot `semi-.dry gas and of `cool wet tar into the top of a' vertical shaft,` passing the gas and tar downwardly through the shaft in direct heat ,transferring relatic'nship,1 utilizing the cool `tar toV condense andscrub'outhigh boiling hydrocarbons from the gas and simultaneousn ly `utilizing the hot semi-dry gas to separate `and evaporate water` from the tar, collecting i dry tar atthe base of the shaft and condensing `wet tarfrom the moist gas after it leaves `the shaft, `iregulating the rate at which said wet4 tar is introduced intofthe shaft in accordance with the temperature ofthe gas leaving the `hase -of the shaftyand maintaining'the temperature of the gasl leaving the base of the shaft slightly above its dewpoint. i

5. AV method of dehydrating -tar which ycomprises 'introducing regulated volumes of i unscrubbed `fuel gas containing superheat with respect to water vapor, and of `wet tar,

simultaneously into the top' of a verticaldehydrating shaft, passing the gas and tar through the shaft to dry the tar and cool and Ascrulo out condensible hydrocarbons from the gas,' i Vremoving substantiallymoisture-satu- :rated from the bottom offthe shaftat a temperature above its 4devvpoint, subsequently cooling thegas below its dewpoint and scrubloing outvmost of its remaining condensible y contents,` in the form of wet tar, collecting `and partially drying said wet tar, introducing the `semi-dry tar thus obtained into the top of the `dehydrating shaft in admixture with` fresh the emulsion at the base of thestandpipe, and

an oiftalre leading off from the standpipe immediately above said seal pot for carrying off .cooled gas and volatilized constituents of the `emulsion therefrom.

7l An apparatus for selectively separating `liquid emulsions into their highand lowaoiling constituents comprising a vertical standpipe, a main connecting the top of the "standpipe with baiiies making a tortuous pas-` sage therethrough to a source of supply of ture of-the moist gas emulsion7 meansforl removin gas containing superheat with respect to the low boiling constituent of the emulsion, la supply pipe connecting the top of the standpipe` with a source of supply of emulsion, said pipe having attached thereto a-device for introducing emulsion in an atomized form into the standpipe, means for dispersingthe emulsion through a current of the hot gas flowing downwardly through the standpipe .to eifectan efficient heat-transfer between gasand emulsion and vaporization of the lowboiling constituentof theem'ulsion,A a seal pot at the base ,of the standpipe for collecting high boiling; non-volatiliz'ed con-n stituents of the emulsion, anda dra-Wolff conduit leading of from the base ofthe standpipe above said seal pot for removing gas and vaporized low-boiling constituent from the standpipe separately from the high i boiling constituent.

f SJAn apparatus for dehydrating aqueous emulsions comprising a vertical -standpipe, means for introducing superheated dry gas into the top of thestandpipe, meansfor` simultaneously atomizing a. regulated volume of aqueous emulsion'intothe top of the standpipe, means for passing the gas'and emulsion downwardly through the stiandpipe,` means foi` thoroughly dispersing the emulsion `through the downwardly moving gaslstream to insure an eiiicient transferv of heat and ivaporization of `water `fromthe emulsion, meanslfor removing gas and water Y `vapor from the base of the standpipe separately Afrom the dry higher 'boiling constituents of the emulsion, and means for governing the rate at which emulsion isintroduced into thestandpipeaccording to the `temperaleaving thebaseof the standpipeij 9. An apparatus Afor dehydrating aqueous `emulsions comprising a dehydrating shaft, `mea-ns forlintroducing a current of gas containing superheat with respect to water vapor into the top of the shaft, means for atomizing a regulated volume of aqueous emulsion into the gas-atthe top of the shaft, means for intimately contacting the gasfand emulsion during theirfdownward passage through the shaft,` means at the hase rof the shaft for collecting dry constituentsof the g gasand' water evaporated from the emulsion separately from said water-free constituents, andmeans for controlling the rate at which emulsion `is introduced `into the shaft tor maintain the temperature of the out-going moist gas slightly above its dew-point. l y Y 1 10.4 An apparatus" for dehydrating-l tar Hcornprisingla vertical standpipe,` a fouligas mainf connecting the topof the standpipe with Va 'gas generator, a conduit connecting the llovver portion of the standpipe;with`k a gas condensing'Iy and'` tar-scrubbing* unit,

Pmeansn for atomizingwet tar 4precipitated i .va-pers, means for lcondensing the Water Y .into @the shaft'.` Y

lfrom the gas in the condensingand Scrub- -bing unit into'a current of hot drygas from .the .generator vat the top of the stand-pipe, a dry tar trap at the base of the standpipe,

Vvmeans Acontrolling the rate at which tar is jfed into the staiidpipe, said coiitrollingmeans being governed according to thetemperature off the moist-vas leaving the standpipe.

1l. An apparatus for separating aqueous emulsions into Water andhigher boiling constituents comprising a shaft having an inlet ,-orcool emulsion and an inlet for super- Vheated gas at its top and separate outlets neariits'fbase -or high 'boiling constituents jofthe emulsion and Vfor the gas andv Water vapors from' the gas, meansfor periodically introducing Water into the -top of the shaft yand means governed by the temperature of the outgoing gas for `Controlling the rate iat which emulsion and Water is introduced 12. .An apparatus for dehydrat-ng Ytar comprising a gas generator, a tar dehydrat- 4ing and gas-condensing shaft and a gasconi fdensing and scrubbing unit, means ioriconducting a currentiof hotsemi-dry gas -from .theigene'rator through .said shaft and thence through the condensing and scrubbing unit, v means for collecting vWet tar precipitated from the gas in said condensing and scrub- ;bing unit,r means 4for introducing Wet itar :from said collecting meansthrough-an atomizger into the rcurrent of gas entering the.

ishaftfmean's ttor Vcollelctingtar dehydrated 4.bly/said gasfandtarcondensed ,from said gas Within the shaft', .and means governed by .the temperature of Vthe moist gas leaving the `rtar dehydratingand gas condensing Shaft for controlling the rate at Which Wetztar 'is introduced into the shaft.

V,13. A method .of separating ailiduidemull `sioniintoY its high and lovv boilingconstitu- -.ents comprising intimateiy contacting the ,emulsion with a uniilovv currentojf gas containing super heat with respect to the vapor of the floWboilingv constituent of ,theY emulsion *for period of time suiiicient to effect selective evaporization ,of said lowiboiling con- .stitutent, subsequently separating .the gas -and vaporized low boiling constituent from the high boiling constituent, yand controlling the volume ratios of gas and emulsion thus contacted and the period of contactto mainsaid gas andfeniulsion to pass-downwardly througlisaid conduit in Vintimate contact, rseparateV :means for removing Vthe high .boiling constituents of said emulsion andthe gas admixed With the vapors of the low boiling constituent from ,the base of said conduit, yand separate means for controlling the volume ratios yof gas and emulsion passed through saidconduitrand the period of contact of said gas and emulsion in'said coiii"'f' duit, at least one of the said means being :under the control of devices responsive to the Vtemperature of theadmiXed gas and vapors of said low boiling constituent leaving theVV base Aofsaid conduit. i Y y 1 5. The method ofiseparating liquid emulsions Ainto their high and low boiling con-V stituents which comprises atomizing a-regulated volume of theremulsion into a stream of hot gas Containing superheat with respect to the vapor ofthe lov:r boiling constituent, fdispersing the emulsion-through the hot gas and passing both Adovv'nWardly through'a dephlegmating shaft in intimate heat transiferringY relationship to evaporate said low boilingl constituent, `separately removing the high boiling constituent and the/gas Vand vapors of the low :boiling constituentfrom the b aseof ,the sliaft,and automatically govperature ofthe gas. leaving the base of the tacted therewith that the said heat will 'effect'substantially complete vaporization of the iWater frompthe emulsion whilev maintaining thesaid gas in an unsaturated condition With respect to moisture at the minimum temperature reached during contact thereof with the'tar. i

ei-ning the rate at-Whi'ch'the emulsion isiiitroduceld into v thes'liaft to maintain the ,tem-

:1n-'testimony lwhereof I Aaffix my signature. i is Annie-En JOHNSON.

ltain `the temperature lof the separated gas slightly fabove its .dew-point `vvithrespect to .the vapor oisaidloiv boiling constituents.

14.' Apparatus .for separating-an emulsion into-its high -and loWV-boiling constituents i comprising an upright Conduit, means for intr'oducing ,emulsion i at the top of saidA conduit, means-for introducing gas containing Y superheat 1With respect to the vapor of the low boiling constituent of said emulsion into ithe top .of 'said conduit, means for causing 

